


It's a Long Story... Full of Sin

by RiseiTekiSensei



Category: Undertale (Video Game)
Genre: All warnings will be at the beginning of each chapter, F/M, I'm Going to Hell, Part of: It's a Long Story Series, Soriel, but i'm not going to add it because this fic covers the whole timeline, i am the trash who writes, the plot is in another fic, this is just porn, this is just sin, yeah...
Language: English
Status: In-Progress
Published: 2017-01-19
Updated: 2017-01-20
Packaged: 2018-09-18 06:55:53
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 2
Words: 4,708
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/9373136
Author URL: https://archiveofourown.org/users/RiseiTekiSensei/pseuds/RiseiTekiSensei
Summary: This is the explicit portions of another series I am writing (the fic is rated Teen, but I'm not). That's it.The first chapter is just an explanation about what this fic is, so you can read that for more info without the risk of R-rated material.





	1. Explanation (Not Explicit)

Um... so you clicked on this fic.

 

It's just gonna be smut.

 

If you're still here, then explanation time:

 

I'm currently write a series called It's a Long Story and the multi-chapter fic I'm currently working on is called "Take a Deep Breath". The chapters in **this** story are excerpts that I'm not going to put in the main story for two reasons: 1) That fic is rated Teen and so is the main story's plot, I don't want to exclude people from reading it because I'd have to give it an Explicit rating for a handful of chapters. 2) My beta for "Take a Deep Breath" doesn't like smut, or at least she doesn't like Soriel Smut, so I'm not going to subject her to it.

 

As far as I know this fic will only ever be Soriel smut; sorry to the people who were hoping I'd jump into other characters' relationships more, I'm not. It will also tie heavily into the other fics in my series so there might be spoilers if you've read one of these chapters before you read one of the one's in the main fic. However I will try not to introduce things in this fic that will be important to the main series. [Note: I WILL introduce stuff that is relevant to anatomy and the like in this fic, but I don't see those details being necessary in the main fic ;)] Also I will indicate at the end or beginning of the main series chapter, if a sin chapter has been written that belongs before or after the main series chapter.

 

For all main series readers: If I put something in this fic that you think I should mention in the main story, please Iet me know! I don't want to deprive the main series readers from any info you guys think is important.

 

However if you don't want to read the main series fics, then it shouldn't hamper your ability to read the sin! Just go for it!

I know I have days when I just need to read some pointless smut.

 

Also I like the idea of magical... *cough* anatomy... 

_I know, I'm trash._

**BUT** not all of the chapters will revolve around it! So there will be things like soul-play, magical sensitive, etc. I will post the warnings/tags for the kind of smut and stuff in the author's notes at the being of each chapter so you can skip it if you don't like that kind of smut. Also I will indicate where the sin chapter falls in the main story by using the story's acronym and the labeling it Ch #.5 in the chapter title so you can tell exactly where in the timeline the chapter occurs.  I will label the fic and the chapter location in the author's notes as well.

EXAMPLE:

Chapter 2: TaDB Ch 5.5, [A Bad Joke, normally]

_Author's Notes_

From: Take a Deep Breath

Chronology: in between Ch 5 and Ch 6

Title: [A Bad Joke, normally]

Tags for this chapter: [whatever i need to put]

[THE SIN]

 

Okay so I hope this clears every thing up!

 

The next chapter will be smut.


	2. TaDB: Ch 5.5 - Eye Opening

**Notes for the Chapter:**

> From: Take a Deep Breath  
> Chronology: in between Ch 5 and Ch 6
> 
> Title: Eye Opening  
> Tags for this chapter (in no particular order): Magical Stimulation, Fisting, Not The First Time, Partner Exploration, Grinding without Penetration, Magical Body Fluids, Minor Edging, Minor Restraint, Minor Soul-play, Magical Tongue, Incomplete/Repressed Orgasm, Fantasizing Induced Guilt, Swearing

She was straddling him. But she wasn’t trying to put her full weight on him, so she lightly pressed her hips against his pelvis. His soul spluttered at the sensation: bare flesh and fur enveloping naked bone.

He tried to rock his hips against her, just to increase the friction. In response, she settled a little more firmly atop him, effectively pinning him to the mattress. He groaned a bit at the increased contact, but mostly it was in frustration at being pinned. Her lovely, **sharp,** ** _damp_** fangs glittered as she flashed him a coy smile. She leaned forward some, shifting more of her weight onto the large paw she had placed just above his head. The same paw that captured both of his smaller hands, again effectively pinning him underneath her.

She had an unfair size advantage and she knew it.

God, it was so hot.

“tease.”, he panted at her, very glad that his voice didn’t crack or sound breathy. Which, all things considered, he really didn’t understand why it did any of that in the first place. Both of those things implied a throat or lungs, ones that he **didn’t** have, and yet his magic still replicated them, because they were the kinds of sounds voices made. Magic was weird.

Her glossy lips peeled back revealing more sharp pearly teeth. “Why yes, love~”, she crooned as she towered over him. Her bare breasts jiggled with every breath she took and the kind assistance of gravity. “I _am_ trying to **tease** a reaction out of you.”

They grinned at each other for a second.

Then she ducked her head down and he lifted his up, trying to meet her halfway. Parted lips pressed against parted teeth. Her tongue was warm and soft and tasted like toothpaste. His magical one probably felt cold to her, as for taste he wasn’t really sure what his magic tasted like, but she **really** didn’t seem to mind.

Eventually she pulled away gasping for air. Not really something he’d ever concerned himself with, but as he watched her chest heave he found that he was rather fond of its side-effects. She caught him staring and snorted. With her free hand she poked his nasal ridge and giggled, “I am afraid to say but you, my dear, are quite the perv.”

Sans raised a brow at her, “says the gorgeous equally-naked goat-monster straddling me.”

She rolled her hips against his. He gasped.

“Oh, I did not say you were alone in that boat…”, then she leaned down her snout brushing against the side of his skull and whispered, “No, we get to share that joy… over and over and over~”

His soul thrummed, still not quite tangible but definitely working on it. “Now, let me see if I have this right~”, she began before trailing her clawed digit down the length of his sternum. “Your bones can be very… **sans** -itive, yes?” Then, as if to prove her point, she dipped a finger between his fifth and sixth ribs right near his sternum. Sans’ wordless non-breath plumed from his mouth as a mist of emotionally charged magic. Even to his own senses it sounded a little like a plea. He arched upward, trying to feel her finger push deeper into his chest cavity, but her hand moved with him keeping the contact shallow and light.

“And eventually your soul will materialize…”, she hummed thoughtfully. Sans thought about cursing- or using a little magic to flip their positions. She continued in that same semi-curious, but mostly taunting tone, “Which I can manipulate with a little magic and pressure~” Again, she punctuated her statement with action. Her magic was hot and charged and erotic. He moaned. He could feel it race down his arms. He could feel it lazily coil around his ribs. But god, it rocked through him as she pressed her hips snugly against him. Her wet soft flesh parted around bone. All of her magic flooded with her emotions and her heat. _lust, longing, love._ And then she let up, leaving the aftereffects of her magic as faint tingle across his bones in her wake. He panted, blue puffs of magic hung in the air above him. He could feel more his magic fizzling across his cheekbones.

When she bent down to gently press a kiss to his skull, her damp white fur shimmered in the blue-ish light emanating from his ribcage. He was close, but not quite there yet. But, **fuck** , did he love the way it looked.

 **His** magic illuminating her exposed figure; all soft curves and fluff hiding layers of muscle, brightened by his magic. He grunted a little and tried to shift in her grip. “And of course~ something I find rather interesting, the marvelous way your anatomy allows you to change to- _better_ suit your partner’s. Quite a courteous thing, if I do say so myself.” She shimmied torturously against him. Giving him the friction that he so badly wanted, needed even, and then taking it away. The moan she pulled from him was louder than before.

His face flushed a deeper blue and embarrassment flooded him. He had to look away from the masterpiece above him, he needed to get a grip or the fun would be over before it began. She loosened her grip on his hands, not letting him go, but giving him some room. Her free hand caressed his face gently… sweetly, no lust or desire in it, just a loving touch to get his attention. He glanced back towards her and her enchanting mahogany eyes so full of concern. “Sans, love? What is wrong?”

He shook his head, he didn’t want to voice his embarrassment. The warmth that spiraled across his cheekbone was so very different from the way her magic had felt before. _trust, love, comfort_. It made him look back at her and her beautiful eyes, her expression hadn’t changed. “i-i’m-”, his voice cracked a little. He made a throat clearly noise and started over. “i’m just a little embarrassed…” He felt ridiculous for even saying it.

“Of what?”, she asked.

Sans coughed a little. “um- by this…” he half-whispered, while he wiggled a little for emphasis.

She cocked her head at him, “But Sans this is not the first time we ha-”

“no, no. not about the sex part,” Sans tried to clarify. “it’s just that... how much i want you, how much i **need** you. how i’m already so close and we’ve barely started…” Sans sighed before continuing, “i’m just not in control of myself and all i can do is want you… it’s embarrassing that i can’t keep it together for very long.”

She kissed him. It was the same soft, sweet thing as before but this time she pressed her lips to his teeth. “I love you. I just wanted to say that first.” Toriel began, “As for your embarrassment, stamina is a thing that can be learned. Through lots and lots of **_practice_ ** . And as you may know I am a very good teacher~”, she hummed lovingly as she nuzzled him. “And for the rest… Sans I do not think you know how gratifying it is, how **_deliciously_ ** **wonderful** it makes me _feel_ \- to know that you want me. I know that being loved or wanted should not be a form of self-validation, but it makes me feel… important and special and self-assured. So knowing that you _need_ me, that you _want_ me so badly that you almost cannot take it…” She hummed a little, like she was trying to clear her throat a bit. “It makes me feel so- so **aroused**.” She explained. “I mean, can you not feel it in my magic?”, she questioned mischievously, only to start flooding his senses with her magic.

In slow undulating waves, she rocked his mind with her wants and needs and lust for him. With the hot erotic sweeps of joy that filled her every time he moaned for her. His words came out a groan, “toooorrrieel-” She started rocking her hips against his, but this time she moved with the waves of her pulsing magic.

From his angle he could see the entirety of her as she pushed herself more snugly around a ridge on his pelvis. From the deep magical flush that spread across her skin and shone through her fur, to her wonderful breasts and taut nipples, to her quivering her lips and parted fangs, up to the fluttering of her eyelids over her passion filled ruby eyes. She was this enormous stunning woman sitting astride him and was fucking him with as much desire as she had love.

But this wasn’t quite right. This wasn’t what either of them needed right now. His planages tightened around her hand to get her attention, because he really couldn’t speak just then. She stopped. It took him several moments to catch his ‘composure’ ,as she liked to say, before he could form coherent words. “thanks- for that- but it isn’t- what we need. not right now. we need **more** , i-i know you can feel it.”, Sans panted pointless breaths at her.

She smiled greedily down at him. The look alone was enough to make his soul throb. “Do you not need more convincing that I find your embarrassment and desires, _erotic~_ ” She asked, her voice low and **very** suggestive.

He squirmed under her hungry gaze. He definitely brought this upon himself, and he was **loving** every second of it. “um- not exactly. you’re probably gonna have to keep reminding me- you know, later on. about your feelings towards my needing you like...”

“-A drowning man needs air.”, she supplied. “Gladly, my love.”

But the phrase caught his attention and something devious swirled through his mind. “ya’ know, i don’t actually **_know_ ** what that’s like…”

She seemed to have caught the change of his tone, but she didn’t see where this was headed, _not yet_. “Oh, is that so?”, she inquired softly as she leaned down. Her hand tightening around his again, holding him down. Her unoccupied paw came to rest ‘oh so casually’ on his sternum again.

“yep.”, he popped the ‘p’. “i mean i don’t need ta’ breath… so when i go down”, he let his blue magical tongue slip out of his mouth. With a bit of effort, he managed to make it longer than it usually was. “... i can stay there for as long as it takes. riding through the waves over and _over_ …” His tongue flicked the soft fur under her chin and he went on, slower now letting his words sink in. “... and i _really_ don’t mind getting all **_w e t_ **.”

Now, it was his turn to flood her with magic. It raced up her arms, blue and yellow curls of it dancing across her fur. She whimpered. Sans pressed his hips against hers, grinding as best he could under the circumstance. “S-sans!”, she moaned as her hips rocked with his. He cranked up the magic. Her panting breaths were hot against his face. He smirked at her. She opened her mouth to retort, but he sent another wave of magic coursing through her and her words mutated into an incoherent moan. She rocked harder, her fingers tighten around his. His hands were really stuck now, but he just gripped back and kept up the heat, so to speak.

Her pants were loud and it soundly like she was trying to say his name with the little gasps of air she had. He was going to follow up with a smug comment about being pinned and yet he was still able to drive her wild, when her clawed digits dug into his ribs. Her furred fingers slipped in between his ribs as her hand clenched. This time his words lost shape to a moan. Through half-lidded eyes she returned his smirk.

She thought that she was gonna take back the control. She would be wrong.

Sans didn’t think she realized how much magic he actually had. All of the other times they had done this, it had been slow and gentle and tender. They had been learning each others bodies not trying tease the other one over the edge fastest. She hadn’t seen him reach his limit yet, and with the way her stomach and thighs were clenching she wasn’t going to tonight.

“toriel-”, he all but whispered, his voice was ragged and deeper than it usually was. She bent down to him, both still rolling their hips. He didn’t let her get all the way down. Again, he found himself truly appreciating their size difference. Her breast had come down closer to his face and using his longer tongue he lapped roughly at one of her bare nipples. Then he changed the pace of their movements: faster, harder. He sent wave after wave of magic from his pelvis right to her center. It wasn’t the same as being inside of her, but god did it get the job done.

Her roar of pleasure, made his soul quiver in delighted anticipation. Her revenge was going to be glorious. Her hips kept rocking as she rode out the waves of her orgasm, but her thighs had tightened around him and he could feel his bones getting wetter. It made the fiction quite distracting. Her warm magic infused fluids pooled on his bones and sent visions of what was to come dancing through his mind. But he still slowed his gyrations with her, she was very sensitive and he didn’t want to push her pleasure into discomfort.

After several more beats of panting silence she finally asked, “H-how long- can you- do that?”

He grinned at her, the magic of his fully manifested soul glittering off of her damp fur. “dunno... wanna find out?” They both let out little breathless laughs.

“Another time, perhaps. As for now~” she answered, her voice teasing again. His soul thrummed. The hand she had on his ribcage began to slowly trail downward, coming to stop at the end of his sternum her fingers curling underneath it. They pressed into the magic filling his ribcage. He whimpered and his magic sparked brighter; his soul glowing like a beacon. “I would very much like to play with something and little more- _provocative_ … _May I?_ ”, she whispered for his permission.

His eyelids fluttered closed and he nodded. Her hand pushed slowly through the magic pooled in his chest; it was meant to be a natural barrier to keep his soul protected from the elements. It gave to her imploring fingers, slowly letting up the pressure so she could reach farther inside. He arched up with a gasping breath. This part was almost as too much for him, her slow careful movements, the almost unbearable warmth of her magic, all **hers** . Sans didn’t think he’d ever let another being touch his soul, but Toriel was not like anyone he’d ever met. Even now with her hand literally in his chest, he still felt safe and loved… and so incredibly **_close_ **.

It was this terrifyingly wonderful combination of anticipation, intimacy, and raw unfiltered magical pleasure that was doing him in. Without a barrier of dust and his own magic, he could feel her so intensely, and not just her hand. All of her, her wants and emotions and the little flashes of what she was going to do to him once she had his soul. He moaned. Loudly.

Sans felt the shiver of giddy delight roll through her at his wordless want. He could even tell that she enjoyed the way his voice made the hand she had inside his ribcage tiggle with the vibrations of it.

Now, her fingers were a hair’s breath from his soul. He wanted her to take it. To touch him, to make him beg for release, to push him toppling over the edge. Her claws pressed delicately-

He woke up.

 

.

.

.

 

His eyes fluttered open and saw a familiar ceiling fan turning lazily. The blue glow filling his ribcage spilled out through his shirt and dimly lit the darkened room. If someone could seem him right now then they’d be able to see all of his ribs silhouetted against the shirt that clung to his slightly tacky bones.  He didn’t produce bodily fluids, but he still managed to get sticky.

Sans felt like life was placing bets against him… and was winning.

 

_what the hell._

 

He could feel his soul quivering with anticipation, he was breaths away from an orgasm… and he had woken up. If there was a benevolent sapience out there somewhere, it would have let him finish before waking him up.

He laid perfectly still for a while and tried not to think about Toriel. He tried not to think about her magic dancing over his bare bones or the sensation of her bare fur and flesh pressed against him or the way her taut nipple had tasted-

His soul pulsed, he was so painfully close.

Fuck. He knew that he liked her. Hell, he’d even started to maybe come to terms with that awful, ‘not going to go anywhere good’, tidbit. And he was perfectly- painfully aware that he found her attractive, but this was ridiculous! He shouldn’t be just- just using the idea of her, the idea of being with her. Of being able to touch her and taste her, of the way it had felt to have her hand inside him, her magic so intense and hot and blindingly arousing-

His bones rattled audibly as he shivered in anticipation of things that- **_weren’t_ ** _gonna happen. ever._

He took several deep breaths again and tried to recollect himself. He was **not** going to masturbate to the thought of her. It wasn’t fair to her or to himself. He just needed to calm down.

.

.

.

After several more minutes of stillness, he rolled onto his side and made to grab his phone and regretted it immediately. His bones were still too sensitive and the mere shifting of fabric across them made his soul thrum. All of that effort shot down the drain as his soul was back at the edge dancing on the cusp of release. It made him a little nauseous. He wasn’t some kid who was crammed full of rampant and uncontrollable emotional shifts. He should have be able to keep himself in check better than this!

He sighed. He knew it wasn’t exactly fair to be upset at himself over his subconscious, but still…

He tapped the phone on and glanced at it’s digital readout.

 

_6:02 AM_

 

Which meant two things: A) the sun should be up, and B) Papyrus should be leaving for his morning jog any second now. Sans figured he just have to wait before trying to move anymore, until after Papyrus had left.

Sans could see light haloing the thick dark curtains hung over his only, _eastward_ , window. He’d hated that window when they had first moved in and then Toriel came and went, leaving the curtains she had hung behind. She’d wake up every morning and open them when she was ready greet the day. Sans didn’t think they’d been opened since she and the kid had moved out… well, at least not by him, anyway.

Thinking about her still wasn’t the best idea. Magic pulsed and throbbed in his bones, begging for contact, for any kind of touch to start the cascade of pleasure. He took slow deep breaths. His shirt clung to his bones. He wasn’t asleep now, so he’d damn well control himself.

But his thoughts kept circling back to her- and him- and Halloween. He could still feel the way her belly had pressed against him, her stomach clenching in anticipation. Her stunning red eyes so close to him that he could practically feel her watching him, studying him. Her words still clung to him, _‘You would just love that, wouldn’t you?’_ Yes, yes he would have. He had know exactly what he wanted to do to her, what he’d wanted her to do to him. He’d thought about surprising her part of the way through their kiss by spreading his legs, letting her press closer. He’d hoped to even push off the damned bar and continue the kiss in her soft and inviting lap.

 

*Cla-thump… Kir-cha*

 

Papyrus had just closed and locked the door behind him. Sans lay in bed for several more minutes as he pulled himself together, pushing all thoughts of anything that was even partially related to Toriel from his mind. It didn’t leave him with much to think about.

Finally, the blue light started to fade.

Eventually, he dragged himself out of bed and shuffled across the floor towards the door. The room was a mess, but that wasn’t really new. He bent down and scooped up a nearby towel, he sniffed it. _welp it doesn’t smell dirty…_ He slung the towel over his shoulder and made for the door. His eye lights caught something flash in the corner of his vision. His phone was blinking a little green light at him. He had a notification of some kind.

He ignored it. It could wait until after he was less of a mess. Besides anyone who messaged him should know he wasn’t awake at this hour and could, therefore, wait.

Bare metatarsals meandered down the hall towards the bathroom. He flicked on the light and closed the door. The fluorescent bulb flickered to life, filling the small bathroom with the yellowish light the old bulb housing produced.

Sans looked at himself in the mirror. His reflection looked back.

He looked like a mess.

The thing about solidified magic was that it pretty much dissipated into the environment. But when large amounts of it were released consistently over prolonged periods of time then it couldn’t evaporate fast enough to keep up with the forming residual build up. It didn’t really stain, but it was damp and left dark wet spots on his clothes. He was very glad for black short just then, because if his shirt was anything to go by then his shorts were definitely worse. The magical residue had condensed- eh, coagulated onto all of his bones leaving them with a sickly sheen.

The bags under his eyes could have been worse, though. He poked at them a bit and snickered to himself at the thought of any of his human friends watching him poke seemingly rigid bone like it was malleable. Humans didn’t get how skeleton-monsters worked… actually, most monsters didn’t get it either. The purplish stains under his eyes would likely be there forever, but as of late they had been less noticeable. Maybe he was actually starting to recover.

Sans leaned into the shower and started it up, he needed to let the water heat up. Just because he didn’t get cold, didn’t mean he liked it. Besides warm water was better at dissolving jellied magic.

As he stripped he ignored the way his clothes clung to him with the same amount of vigor as he ignored the cracks along most of his bones. He was like a walking catalog of bone fractures and bad ideas. But with all of his active sensory evasion, his thoughts circled back.

Toriel.

He just didn’t know what to do with this- this new… information. He liked her, and that was fine, it was manageable. She was nice and funny and polite, it was to be expected and he knew nothing would come of it. They just weren’t compatible like that and he’d just have to deal with it. Fine, good. He could do that…

But **this.** Wanting her- not just her company or friendship, but her body and-

Sans shivered.  And tried to push the rest of it from his mind. Nobody should expect him to come to terms with any kind of life changing situation until after he’d had coffee, all of this could wait. Besides, this, what he was feeling, was probably just because of Halloween. Because of what had almost happened- _when we were drunk and couldn’t think properly…_

 

 _so what’s your excuse for_ **_dreaming_ ** _about her, smartass?_

 

Sans puffed out a sigh and kind of hated himself sometimes; especially, when he was right…

 

_at least, i haven’t had any nightmares- memories- whatevers in the last few days, so that's-_

 

And then his brain stopped functioning as a thought dripped into it, slow as molasses. Gumming up everything inside with its horrible hypothetical.

 

_was that just a dream-_

 

Peripherally, Sans realized he was watching a slow motion version of his face make the ever iconic ‘oh shit’ expression. Eye orbits widening, eye-lights expanding, perma-grin pull down into a shocked grimace. The blush was unique to this particular ‘oh shit’ moment, though. It started right over his nasal bridge and slowly spread across his cheekbones via blue wisps of magic. From the center out.

 

_-or was it a memory from different loop?_

 

 _...a very_ **_very_ ** _erotic memory…_

 

_…about me and- toriel…_

 

God, he was really gonna need this shower.


End file.
